{"id":1137,"date":"2004-11-16T10:30:00","date_gmt":"2004-11-16T09:30:00","guid":{"rendered":"https:\/\/kids.esa.int\/death_of_the_dinosaurs\/"},"modified":"2026-10-08T00:36:26","modified_gmt":"2026-10-07T22:36:26","slug":"death_of_the_dinosaurs","status":"publish","type":"post","link":"https:\/\/kids.esa.int\/fi\/death_of_the_dinosaurs\/","title":{"rendered":"Dinosaurusten sukupuutto"},"content":{"rendered":"
\n

Maa on liikkuva kohde ampumaradalla. L\u00e4hes joka p\u00e4iv\u00e4 pieni avaruuskivi ohittaa planeetan muutaman miljoonan kilometrin et\u00e4isyydelt\u00e4 \u2013 usein huomaamatta. Joskus ne tulevat l\u00e4hemm\u00e4ksi kuin Kuu.<\/p>\n<\/div>\n

Tutkijat arvioivat, ett\u00e4 Maan l\u00e4hell\u00e4 voi olla jopa 100 000 asteroidia, joiden halkaisija on yli 100 metri\u00e4 \u2013 eli jalkapallokent\u00e4n kokoinen. Yli 600 Maan ohittavaa asteroidia, joiden halkaisija on yli 1 km, on jo l\u00f6ydetty. Satoja muita on viel\u00e4 l\u00f6yt\u00e4m\u00e4tt\u00e4.<\/p>\n

Muutaman tuhannen vuoden v\u00e4lein jokin asteroidi todellakin t\u00f6rm\u00e4\u00e4 maapalloon. Viimeisin tapaus sattui Siperiassa vuonna 1908, jolloin pieni asteroidi tuhosi yli 2 000 neli\u00f6kilometri\u00e4 mets\u00e4\u00e4. R\u00e4j\u00e4hdys olisi tuhonnut Pariisin tai Lontoon kokoisen kaupungin.<\/p>\n

Hyvin harvoin tapahtuu t\u00f6rm\u00e4ys, joka tuhoaa el\u00e4m\u00e4n suuresta osasta maapalloa. 65 miljoonaa vuotta sitten 10 kilometrin levyinen asteroidi aiheutti r\u00e4j\u00e4hdyksen, joka oli voimakkaampi kuin kaikki maapallon vetypommit yhteens\u00e4. Se kaivoi Meksikoon 180 kilometrin levyisen kraatterin ja levitti tuhkerroksen ymp\u00e4ri maailmaa. Laajat tulipalot, joita seurasivat pimeys ja \u00e4\u00e4rimm\u00e4inen kylmyys, johtivat dinosaurusten sukupuuttoon.<\/p>","protected":false},"excerpt":{"rendered":"

Earth is a moving target in a shooting gallery. Almost every day, a small chunk of space rock passes within a few million kilometres of the planet \u2013 often unseen. […]<\/p>\n","protected":false},"author":5,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"esa_banner_image":"https:\/\/www.esa.int\/var\/esa\/storage\/images\/esa_multimedia\/images\/2000\/10\/artist_s_impression_of_a_catastrophic_asteroid_impact_with_the_earth2\/17866156-3-eng-GB\/Artist_s_impression_of_a_catastrophic_asteroid_impact_with_the_Earth.jpg","esa_banner_description":"Artist's impression of a catastrophic asteroid impact with the Earth","esa_banner_credit":"ESA","esa_banner_licence":"ESA Standard Licence","esa_banner_detail_url":"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2000\/10\/Artist_s_impression_of_a_catastrophic_asteroid_impact_with_the_Earth2","esa_external_url":"","esa_external_new_window":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":true},"categories":[46,10,11],"tags":[2],"panel":[],"language":[],"age":[],"duration":[],"resource_type":[],"audience":[],"wf_post_folders":[],"class_list":["post-1137","post","type-post","status-publish","format-standard","hentry","category-comets-and-meteors","category-learn","category-our-universe","tag-background-article"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/posts\/1137","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/comments?post=1137"}],"version-history":[{"count":1,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/posts\/1137\/revisions"}],"predecessor-version":[{"id":2280,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/posts\/1137\/revisions\/2280"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/media?parent=1137"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/categories?post=1137"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/tags?post=1137"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/panel?post=1137"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/language?post=1137"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/age?post=1137"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/duration?post=1137"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/resource_type?post=1137"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/audience?post=1137"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/wf_post_folders?post=1137"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}